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<?php $a = array ( 0 => array ( 'name' => 'test', 'address_1' => 'test', 'address_2' => '', 'address_3' => '', 'address_4' => '', 'postcode' => 'test', 'country' => '1', 'tel' => '123566', ), 1 => array ( 'name' => 'test', 'address_1' => 'test', 'address_2' => '', 'address_3' => '', 'address_4' => '', 'postcode' => 'test', 'country' => '1', 'tel' => '123566', ), 2 => array ( 'name' => 'test', 'address_1' => 'test', 'address_2' => '', 'address_3' => '', 'address_4' => '', 'postcode' => 'test', 'country' => '1', 'tel' => '123566', ), 3 => array ( 'name' => 'test', 'address_1' => 'test', 'address_2' => '', 'address_3' => '', 'address_4' => '', 'postcode' => 'test', 'country' => '1', 'tel' => '123566', ), ); // $acount = array_count_values($a); array_diff($a[0], $a[1]); print_r(array_keys($a));

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